See, I stopped pre-moving after black started playing 1... e5 all the time and I would lose my bishop. Surprisingly I would still win a good half of them because I would just play fast.
This is also why you play Nf3 before e3, then you won't even have the chance. I sometimes will throw out a trick like this once and a while if I'm playing someone who is always pre-moving, but this is why pre-moves in the opening don't work
The first one I've played in bullet and had white premove Nf6 several times. Free bishop. I've had this happen four times.
What if they are smart and don't take the pawn? Well, you know, you just figure something out.